When completing a well it is advantageous to have several screens so that if one screen is blocked the production fluid can flow through another screen, but connecting several screens is not easily performed. In the known solutions, the screens are designed so that mounting of the completion system at the rig is very complicated as the commonly used tools for connecting the well tubular structure cannot be used. Therefore, there is a need for an alternative so that the well tubular structure of the completion can easily be mounted by the known tools at the rig.